A. Field of the Invention
The present invention relates to methods and apparatus used in manufacturing production lines for filling containers such as bottles and cans with liquid food products. More particularly, the invention relates to an apparatus for rapidly filling quantities of containers with a variety of liquid food products which have different viscosities, such as beverages and jellies.
B. Description of Background Art
A wide variety of machines are used in product packaging lines for filling containers with liquid products. Ideally, such machines are capable of filling large quantities of containers with liquid products in a short time. In a typical installation of a machine for rapidly filling large quantities of containers with liquid products, empty containers are transported to the machine by an inlet conveyor, where a rotary or in-line arrangement of fill heads dispense liquid products simultaneously into individual containers. Obviously, the through-put rate of this batch processing technique exceeds that of a container filling method in which individual containers are filled one at a time.
After a batch of containers is filled with liquid product as described above, the filled containers are transported away from the filling machine, by an outlet conveyor, for example, for subsequent processing including the installation of caps or lids on the containers, attachment of labels, and placement of the containers into boxes for shipping.
A variety of liquid product delivery systems are used in liquid product filling machines, including gravity or pressure feed, and the quantity of liquid product delivered to a container is controlled by various methods such as timed flow, container fill-level control or volumetric, in which a predetermined quantity of liquid product is dispensed into each container having a predetermined volume.
Liquid product filling machines used in the food and drug industries for filling containers with food and drug products, especially those intended for human consumption, must meet performance requirements in addition to those of liquid filling machines of the type alluded to above. For example, U.S. Food and Drug Administration (FDA) regulations require that machines used to fill containers with liquid food or drug products must be sterilizable, and readily cleaned of liquid products which might be trapped in cavities within machine parts, and thereby providing a growth media for microbes. Accordingly, a goal in the design and construction of production line filling machines for liquid food products is that such machines be Cleanable In Place (C.I.P.), with no or minimal disassembly of machine components required.
Although not required by FDA regulations, liquid filling machines for use with food products desirably would also be able to accommodate products having a wide range of viscosities, including very viscous products such as jellies and low-viscosity products such as beverages. The present inventor is unaware of any existing liquid product filling machine which is capable of rapidly filling containers with liquid food products which have a wide range of viscosities, which also meets C.I.P. requirements.
Machines relating generally to the field of the present invention include: Weiss, U.S. Pat. No. 5,501,253, which discloses an apparatus for filling vessels with liquid. The disclosed apparatus is intended primarily for use in filling bottles with carbonated beverages, and uses a counterpressure fill head that includes a valve stem retractable in a valve body to allow liquid under pressure to flow through an annular opening made between the valve stem head and a valve seat within the tubular valve housing, into a bottle pressed into sealing contact with a resilient seal attached to the lower end of the valve housing. Excess gas in the bottle is evacuated through a central bore provided through the valve stem. No means are disclosed to adapt the apparatus to handle viscous liquid food products, or how to make the apparatus meet C.I.P. requirements.
Kiholm, U.S. Pat. No. 6,135,167, discloses a method and apparatus for a filler valve, which includes a valve stem head provided with circumferentially spaced apart radial ports for dispensing liquid food product from a central bore connected to a produce inlet port, to the interior of a bottle. Air displaced from the container by liquid product injected into the container is exhausted into a co-axial annular space between a tubular slider housing which longitudinally slidably holds the valve stem, the slider housing having at the lower end thereof a resilient annular sealing cap for compressively contacting the rim of a bottle or similar container. No means are disclosed for evacuating excess viscous liquid product from a container being filled.
The present invention was conceived of to provide a machine for rapidly filling batches of containers of various sizes and shapes with liquid food products having a wide range of viscosities.